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Justice. Only Justice Shall Thou Pursue

It's a history of violence, bloodshed, and genocide, which extends all the way into the 20th century when Japan invaded China and Korea and killed hundreds of thousands of people (see the Rape of Nanking). The Chinese aren't particularly forgiving of those acts, while the Japanese are reluctant to acknowledge the war crimes committed by their imperial armies both before and during World War II.

The current dispute reaches back through history, but it also centers on modern needs for mineral and oil and gas resources believed to be located in the waters off the islands.

Though the islands are uninhabited, they are near coveted fishing grounds and potentially large gas reserves, and their status touches on historical grievances in East Asia dating to Japan’s behavior during and before World War II.

Taiwan’s government generally maintains friendly relations with Japan but activists there, as in mainland China and Hong Kong, have made their voices heard in the brewing dispute over the islands.

The Japanese public broadcaster, NHK, broadcast footage that showed a Japanese Coast Guard vessel blasting water at a Taiwanese fishing boat. Another Taiwanese boat tried to spray water back.

The Coast Guard said more than 40 Taiwanese fishing boats and eight patrol craft briefly approached the disputed islands. The boats had since left the waters, the coast guard said.

Tensions between Japan and China erupted earlier this year when the governor of Tokyo, a well-known nationalist, angered Chinese activists by announcing that he wanted to buy three of the disputed islands from their owner, a Japanese citizen. He said he believed that Japan’s central government was not doing enough to defend them.

The uproar over the governor’s threat prompted the central government to buy the islands instead — a move that Japanese officials stressed was to prevent them from falling into more provocative hands. But in China, the move was seen as an effort to assert Japanese control, setting off angry demonstrations. Some of the protesters attacked Japanese businesses.

In an effort to calm the dispute, Japan’s vice foreign minister, Chikao Kawai, met Tuesday in Beijing with his Chinese counterpart, Zhang Zhijun. The Chinese Foreign Ministry said the two sides had talked about ways to handle the dispute but indicated that no substantive progress had been made.

Considering that all the countries involved have significant economic ties to the others, all should have reasons to see the dispute simmer down and end peacefully. However, the mineral and fishing resources are too good to pass up, and that's why everyone's disputing the ownership. There have been anti-Japanese riots in China, where Japanese-owned factories have shut down because of the violence. It's a volatile situation, and it's one that could get the United States involved - even if the US is trying to get things to settle down.

The dispute has also meant China's sent its first aircraft carrier into the field. The reflagged ex-Varyag is seen as largely being a training ship to accustom the Chinese navy to potentially building its own native-built carriers, but it also indicates that the Chinese are willing to put military resources towards defending its territorial claims.

UPDATE:
It should be further noted that while China has sent the aircraft carrier into service, it does so without any aircraft capable of landing or taking off from the carrier, and it isn't likely to have that capability for several years. Of much more relevance to the current situation is the fact that the Chinese military has invested in developing long range cruise missiles capable of hitting naval targets - which could potentially include US Navy ships, as well as expanding its submarine fleet.